Well I am expecting my m16 to be approved any day now, so I am starting to prepare!

I was impartial on whether to get an upgraded trigger or not, as I won't be using the weapon for precision work. However, I decided it may be good to get a different trigger in there regardless, to preserve the original for collectors and value's sake. So I think I will be going with the geissele SSF.

I just purchased a 22lr upper, so should be set there. Although I haven't found an in stock CMMG Auto Sear Trip Kit, so thats a problem. Let me know if you know someone selling an extra or where I can find one in stock!

I haven't decided which 5.56 upper to get for it yet.... But I have a few AR's so I figure I can use one of those in the meantime.

Any other must have's??

The Geissele SSF is a wonderful trigger. I really like mine. I'm a fan of Geissele triggers.. near every AR I have has a Geissele. Only issue I have with it is that I don't believe it is compatible with my Razorback. I read it has issues.. which I am currently having. I plan to change out to a lighter spring first to see if that helps.
Not sure how well it will work with the CMMG 22LR. I haven't had a chance to test mine out yet. On a MCR it works fine.

So your looking for uppers. Here are the ones I'm aware of that: Sadly most are not available new.. hence very expensive.
AM180: Basically a upper that uses a American 180 drum. I have never shot one of these.. but shooting a real American 180 is fun!
Razorback belfed 22LR: Finicky. Haven't really worked out all the issues. Read it could be the SSF trigger. Going to have to change out the spring and milspec trigger to see if it runs.
FM-9: No experience but I want one!
MCR (Shrike) beltfed: Some are finky. When it runs, it is fun. When it doesn't.. it's frustrating. It takes a bit of tuning. It does work with the SSF.
CMMG 22LR Upper with CMMG auto sear: Haven't run it. It may require tuning from reading about it.

I'm in the same boat. Geissele makes great triggers though I have heard good things about the HIPERFIRE Hipertouch Auto Trigger. My only concern would be with compatibility with various uppers (CMMG .22 dedicated and the 9mm Radial Delayed Blowback uppers) and that makes me lean towards the SSF.

If anyone has experience with both, I would really appreciate some feedback.

I've got both. I haven't tried the hyperfire yet. It's been sitting around for a year and I haven't gotten it installed yet.

I went to order the G SSF and Geissele wouldn't sell it to me without an approved F4. That was rather annoying. I ended up sourcing a SSF from Brownells and installed it when my form cleared. Hyperfire happily sold me their auto trigger and even gave me a .mil discount.

Given my other Hyperfire triggers and how my SSF feels, I think I'll like the Hyperfire trigger a little better.

Primary Arms had the SSF on holiday sale for $295 which is the lowest I have found so far.

That's a good price. I think Brownells was $400 and I had a $30 coupon.

I use to buy/sell Geissele as a distributor many years ago.. Black Friday is the best time to buy since the prices would be same as dealer pricing.. If you don't mind waiting that long.
Since pricing got competitive I decided to stop selling due to low margins.

No personal experience with the Geissele SSF trigger assembly, but IIRC, there have been a number of threads wherein it was reported that a change to a lighter spring was necessary to achieve proper function using the Geissele SSF trigger assembly in connection with M16 full auto .22LR operation.  But, as is the case with virtually all M16 full auto .22LR implementations, many factors can effect proper operation.

Disclaimer:  I have no affiliation with or financial interest in any vendor or manufacturer; and I am not a competitive shooter or a blogger who receives any form of compensation for endorsements or favorable public or private comments.  Use of vendor and/or product brand names, if any, is for informational purposes only.

Best of luck.
MHO, YMMV, etc.  Be well.

I have a Hiperfire EDT-SF, home-built CMMG 22LR upper runs great.  Factory 9mm RDB upper I can get some bursts, then hammer follow or light strike? -- haven't diagnosed yet and have only had it out once.  Using the stronger spring it comes with.  My receiver is an old PAWS that's out of spec though.

I recommend testing a Hiperfire if you can. Not all of them are good.. Call some stores to see if they have HF displays. i know some stores have their sample setups.
At one of their booths, I have shot some crappy feeling HF and some quality HF, but I don't know what model it was. I do know it was the more expensive version though.

My SSF ran great with .223 and my CMMG 9mm upper.  It had some timing issues with my .22 upper (worked without issue with original trigger).  I ended up pulling out the SSF as I wanted it to work with all my uppers (without having to tweak things to get it to work).

Thanks for the info. I think I will just try running everything with the stock trigger. I would hate to drop $300+ on a trigger that doesn't play nice with all uppers especially sincet I can only use it in one rifle.

I have the ssf in my RR. It works with all my uppers just fine. The cmmg 22 bolt was working perfectly for me prior to the ssf and one magazine after I installed the ssf the sear trip and firing pin broke. They had been heavily used so it was just a coincidence I believe. I had a very hard time getting the conversion to work again, trying multiple different ammo's and springs, etc. I finally got the bore buddy weight kit and it's as close to 100% as a 22 can be. I really didn't like having nice triggers in all my other AR's and not in my best one. Also works perfectly with the cmmg RDB 9mm.

Congrats, I’m also expecting mine in hopefully in a week or so


for what it’s worth I debated on the SSF trigger & it’s 100% worth it.

Another nice upgrade is the Griffen armament 60/120 M16 selector, it makes getting it from safe to auto and in between very easy compared to the long throw of a traditional selector.
Here is a clip of the selector

Griffen selector gif

It took me a couple of months to find a used CMMG auto sear so start getting your feelers out now. They sold out after the FRT triggers came out

I'll have to look at the Griffin Armament selector. Didn't know they made one.

Well many CMMG auto sears will go back on the market due to the AFT are still pushing forward that they are machine guns.. (They just sent FFLs a open letter stating as such)

yeah me either. I had heard of the vaporware geiselle short-throw m16 selector so i got to searching & came up with nothing, then happened upon a guy on Reddit who turned me on to the Griffen product. It's such a nice upgrade & ambi too.

Arms Unlimited often lists an inexpensive, conventional full-throw ambi selector if ambi is more important than range of motion.

I picked up the BAD-ASS FA PRO for $46 and BAD claims it is 100% compatible with all known AR variant lower receivers. However until my form 4 clears, I will not be able to test it.

I believe that's what I have right now.

I run a SSF in my M16 with a Atchisson/Ciener .22 kit and I don't have any issues with them working together. I believe the CMMG conversion is a direct copy of the Atchisson/Ciener kit but correct me if I'm wrong.
Just a tip, to try to ensure as close to flawless function as possible out of the kit, I took a stone to all the sharp edges on all the parts of the kit and I keep it clean and very well lubricated when I shoot it.
I actually prefer shooting the M16 in .22 than I do in 5.56 and the SSF trigger is a huge improvement over the original parts.
For a budget upper I dug through my parts stash and came up with a M4 upper which I mounted a pencil thin barrel to after I had it cut that threaded at 10". As gas isn't necessary for the .22 kit, I took an old gas tube and cut it off at about 2" and then flattened the exposed part and folded it onto itself to seal up the gas port to make a dedicated .22 upper that my kit lives in.
I run it with a suppressor and it's a lot of fun. I especially like not getting a gas bukkake to the face like I do when I run 5.56.

This is all off the top of my head and subject to addition/correction/criticism: First of all, there are two distinct Atchisson patented .22 conversions for the AR-15/M16 pattern firearms.  The so-called Atchisson MkI is described in U.S. Patent No. (USPN) 3776095.  The MkI conversion was not as popular as the later MkII/III version that is described in USPN 4169329, but all versions come up for sale on GunBroker.  As I understand it, the MII and MkIII sub-versions differ as to the firing pin that is incorporated.  As one can see from the patents, there are many differences between the MkI and the MkII/III.  Ciener worked with Atchisson to develop the MkIII and bought all rights, interest and tooling to it in 1993.  I believe the MkII/III patents expired in 1997.

The CMMG conversion has evolved since its first introduction around 2008.  The initial CMMG product was quite similar to the Atchisson MkIII.  The CMMG product has gone from carbon steel, phosphate coated steel; to including a stainless steel version; to having a version with a brass collared adapter; to going back to all stainless steel; to having a left hand as well as right hand version; to using a standard AR-15 size firing pin cotter pin retainer instead of a tension pin to retain the firing pin (USPN 8316755).  There was also a CMMG version that was Beta tested but, to the best of my knowledge not released for general sales, of a chamber adapter that had a rotating lock to prevent fore/aft frame movement (USPN 8726560).  There was also a modular RH/LH design ("Evolution") that was patented, but not released (USPN 8826797).

The auto sear trip and anti-bounce weight (ABW) are different for the Atchisson MkI and MkII/III versions.  Likewise, CMMG implements a different auto sear trip than the Atchisson versions.  The CMMG ABW is unique (USPN 8590199) as well in that it includes forward assist capability to the conversion unit; and it has to be modified (lug at the rear removed) to be used with early CMMG conversions or with Atchisson MkII/III conversions.  The Atchisson MkII/III ABW needs no modification to perform the ABW function in CMMG conversions.  The CMMG ABW (approx. 0.75-0.8 oz.) is about 0.2 oz. or so lighter than the Atchisson/Ciener ABW.

Disclaimer:  I have no affiliation with or financial interest in any vendor or manufacturer; and I am not a competitive shooter or a blogger who receives any form of compensation for endorsements or favorable public or private comments.  Use of vendor and/or product brand names, if any, is for informational purposes only.

Best of luck.
MHO, YMMV, etc.  Be well.

Some additional differences that have come to mind:
At or about the time CMMG introduced their ABW with forward assist, as well as adding a hole to the frame back plate to accommodate the forward assist lug, they also cut the bottom off the back plate on the conversion frame.  The back plate was previously circular as is the back plate on the Atchisson/Ciener MkII/III conversion.
The CMMG ABW has a deeper notch at the rear where the ABW interfaces with the recoil spring tube than does the Atchisson/Ciener ABW.  The CMMG ABW also has a flat top and feet on the bottom.
Around 2013 or so CMMG started using an extractor with a small notch in the claw.  This is often mistaken as a chipped extractor.  It is a deliberately made feature.
Atchisson/Ciener .22 (steel) conversion magazines are not compatible with the McFadden speed loader, but are compatible with the CMMG hand push loader.

MHO. YMMV, etc.  Be well.

Finally got to shoot my gun at the local FFL/SOT while waiting for form 4 to clear.

I have a dedicated CMMG .22lr upper that I put together with a CMMG trip and weight. Test fired with 2 blackdog 32rd and one 50rd drum. Pleased to say not even a hiccup and the .22lr will likely be my favorite. All fired with suppressor.

Next up was a CMMG RDBB 9mm upper. Ran 4 30rd ARC pmags through it. 3 mags with can on one without and again ran flawlessly.

Stamp cleared last week so I can contribute here now.  Put an SSF trigger in, tested with 5 uppers today.  5.56, 300 blk, 45 acp CMMG guard, and 2 CMMG 22 uppers (16 inch and 5 inch supressed).  Both 22s have the CMMG trip, one is newer ones that are finally back in stock (black) and one is the original silver color.

Every upper ran perfect.  Super pleased.  The SSF has found a permanent home.  Love the feel of it.

The one thing I noticed which is a non issue for me as I don't drop hammer when then lower is off, but on a standard hammer, if one did it contacts the bolt hold open lever vs the aluminum reciever...on the SSF the hammer contacts the aluminum reciever just below the bolt catch channel.  I don't drop the hammer either way but just a little detail I noticed.

I've said it before, and it bears repeating, the Geissele SSF is not designed for, and should not be used with a Colt 635 style 9mm upper.  The SSF is not hardened and will deform over time with the 9mm blowback.  The website says this now, but it didn't when I bought mine.

This whole post will date me and my M-16...

I have a Knight's Armament 2-Stage full auto trigger in my RR and Kuehl .22 upper, no issues.

I prefer the KAC FA FCG over the G'

I might have spoke to soon on the 22 uppers.. they worked at first but now I'm having issues.  I have tried a few things and have some more testing to do, but I will report back when I get it squared away.

I have an SSF in my A2, and my upper built with CMMG parts runs without issues of any kind.  However, to get it to that point I had to do a lot of experimenting with the upper.  I was not willing to compromise anything in the lower to get it to run in 22 (springs, mil-spec vs. SSF, etc.), and it was well worth it in the end.

Then a friend built a 22 upper almost exactly like mine and it ran from day 1 in full auto on my lower.  Go figure ...

I think I got it figured out today. I needed more threadlocker and and cranked down the screw on my adjustable trip.  The non adjustable trip I was using before that worked at first, I think just eventually bent out of timing from use.  I think the SSE might be more rough on the trip in one way or another?    You are correct though, it is worth it to get it to work with the SSF...it is just so much of a better trigger.  The pull weight on auto on a GI trigger is, shall we say....less then desirable.  Way easier to manipulate short bursts with a nicer trigger.  I am hoping this adjustable trip holds up, if so I will ditch the CMMG trips for good.

OK,all this talk about this aftermarket bullshit!When you need this WEAPON to function you will be in a world of shit when your hyperfire or gizzle trigger shits the bed.WTF is wrong with USGI parts that ACTUALLY work?Owned M16 rifles since 1983.Oh yeah,magpul sucks shit too.

SSF is an issue part for SOCOM.

Old school here,my shit works,to hell with the aftermarket gimmicks,do not fucking get this mentality to fuck up good weapons??Shit I give up, to each its own.

SSF works well across three different m16 lowers with a cmmg Ceiner pattern 22lr upper. Another m16 lower with LMT 2-stage FA fcg does not function well with said 22lr upper.




SSF is no gimmick. As others posted, it’s a SOCOM issued fcg. I have many thousands of rounds on several SSF. They are totally reliable. From and engineering standpoint, they are no more complex than the standard M16 fcg. And they make a big difference in trigger control.

Jesus Christ.....

Not trying to be a contrarian here, but I seem to recall that the military issued Geissele "SSF" are machined from bar stock, while the civilian market ones are formed by MIM (metal injection molded). So the two SSF versions would be functionally similar, but very different in metallurgical properties.

I have a hard time seeing Geissele producing a separate part for civilian M16 sales. Very few civilians have M16's and setting up a MIM line for them doesn't make sense if they can't sell it to the military. Given the $400+ price for the SSF I would put money on civilians getting the same model as the military.

After reading through this thread, I noticed that no one mentioned the JP Enterprises single stage trigger. You can use a GI hammer and disconnector. I really like the single function and the use of a standard hammer. Check out   https://jprifles.com/buy.php?item=JPFC-1 at $100. Just a thought.

Scott

I found a post from Bill Geissele on m4carbine.net, dated 7/24/07. He mentioned the different "SSF" trigger used by SOCOM, which is apparently made from bar stock:

(quote)
"Cutting from barstock would add 50% to the cost of the trigger. It will not necessarily make a 'better' part than casting as I have seen my share of defects in wrought material. On the other hand there are more material choices in barstock than MIM (forgings are also made from barstock so there are also more options for forging). This being said I do very limited amounts of barstock select fire triggers for customers in the US SOCOM community....not because they are better per se but they have requirements such that the fixed geometry of my investment castings would need to be changed. In the next 3-4 months you will see the semi-auto version of this trigger commercially available."
(end quote)

The SSF triggers which are available to us are investment castings. They are made with care and precision. Again, here's what Mr. Geissele wrote about his processes:

(quote)
"1. Raw castings have the gate ground off
2. Castings are machined on a Mazak or Bridgeport VMC
3. Castings are hand deburred and critical radii put in by hand
4. Castings are 'Superfinished' which is a process used on aircraft transmission gears to polish a metal surface without removing gross metal or heavily rounding corners.
5. Superfinished castings have threaded holes resized to precise dimensions to account for the prevailing torque screws
6. Sear surfaces on all three parts are cut via wire EDM to +/- 0.0005" tol
7. Components are hand deburred again
8. Components are carburized
9. Components are cryogenically treated (deep frozen to <-120F) for wear resistance and stability
10. Holes are honed to +/-.0002"
11. Parts are blued
12. Parts are assembled (adjustment screws installed and prevailing torque checked, hammer trunnion installed)
13. Parts are fit together in a precision jig that simulates a receiver under full spring pressure st that any minute imperfections in the sears can be felt by hand.
14. Sear engagement is preadjusted
15. Trigger timing is checked, reset is checked, safety operation is checked.
16. All three parts are searialized together
17. Triggers are coated with RustVeto preservative
18. I then hand completed Triggers to my wife Amy for wrapping in VCI paper"
(end quote)

I wouldn't read that post as all SSF's sold to SOCOM are made from barstock. I would read that as a subset of the SOCOM community requested a bar stock version and I made it for them.

I was on the fence with getting the SSF but after speaking to Geissele and them being so adamant about not using it on any 9mm, I called JP about the JPFC-1. CS told me I had to speak with Dave who is their select fire expert. Dave was great and said that the JPFC-1 will not work in select fire without modification but it is the trigger they use in their own full auto guns. Dave was happy to modify it at no additional charge and it took about a 5 days to get it.

There are two screws to adjust overtravel and sear engagement which were really easy to set. JP provides 1 gold reduced power trigger spring and a red heavy spring and a lighter gold hammer spring. I used the red/gold combo however I have replaced my Geissele SD3G, SSA and LaRue MBT springs with the gold/gold springs from JP and have had 100% reliability with them while enjoying reduced trigger weight.

I did polish the trigger and the end result was a just under 4lb pull weight on semi and 6lb on auto with nearly zero creep and overtravel. The nice thing is that if you prefer more creep or overtravel you can set it for your liking. For $123 with shipping and taxes, it's an absolute steal.

I have a SSF somewhere.  

Early on I couldn’t get it to run on a 9mm, most likely a non issue now.  

I went with legit Colt parts (all of it) and never had a lower related issue since.

What was their stated reason for not using the SSF on a 9mm? Is a blowback operating system likely to break something in a Geissele fire control group?


Never mind, I went back through this thread and found the answer:

Another +1 for the SSF. You wont be disappointed. Its so nice having the clear and clean "lines" of a good 2 stage trigger for an M16. Before I launch all those projectiles I dont care to feel any gritty creep or other nonsense. You obtained the pinnacle, you deserve a nice 2 stage for it.

Its also a great feel/fit if you are used to shooting the SSA.

In addition, Geissele said it applied to the CMMG RDB & Mean arms. Their stance was no 9mm period.

I've got a griffin 0-60-120 selector coming in this week. Pretty excited about putting in my 10.5 gun.

Pretty much the only short throw option I know of since G$ won't sell us the FAST selector or whatever they call it.

KAK has good prices on regular 0-90-180 ambi selectors if you just want that.

I'll probably just polish/tune my milspec trigger for now. The SSF sounds nice but I'm not sure I'm ready to drop 300 for it yet.

Im running a Forward Controls Design 0-50-180 ambi selector and love it.  Couple different lever options too.

I have several of the Griffin selector's and they are great!

Sounds like he just can't be bothered to do the testing on them, not that I blame him. That's what we're for.

I use the shit out of mine in CMMG RDB systems with zero issues.